Floating docks are designed to float in water as water levels rise and fall. Floating docks are useful in areas where tides are experienced, and in areas where water levels vary due to such factors as weather, flood control, or hydroelectric generation.
The horizontal position of a floating dock is typically held in place by piles that are driven into the earth. The dock is connected to the piles by pile guides, which permit vertical movement of the dock as water rises and falls, but prevent substantial horizontal movement of the dock.
Pile guides in common use have inadequate service lives. Most pile guides in common use are formed of metal. Metal pile guides are not sufficiently resistant to environmental factors such as weather and sunlight. Particularly in salt water applications, corrosion of metals, even galvanized metals leads to replacement of the pile guides.